Adding and subtracting machine.



.J. L. POOLE.

ADDING AND SUBTBACTING MACHINE,

7 APPLICATION FILED AUG-25 I916- 1y257g9260 I Patented Feb. 26. 1918.

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J. L. POOLE.

moms AND SUBTRACTING MACHINE.

APPLICATION FILED AUG.25, I916.

Patented Feb. 26,191&

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a D DD n10 BUD D D aiwuinflgown/M02 UNITED STATES PATENT OFFICE.

JESSE L. POOLE, 0F RICHMOND, VIRGINIA.

ADDING AND SUBTRACTING MACHINE.

To all whom it may concern:

Be it known that I, Jesse L. Poona, citizen of the United States, residing at Richmond, in the county of Henrico and State of Virginia, have invented certain new and useful Improvements in Adding and Subtracting Machines, of which the following is a specification.

My present invention pertains to machines for making calculations; and it has for its general object to provide an adding and subtracting machine that is simple an inexpensive in construction, susceptible of easy manipulation and reliable in operation and equipped with an organized mechanism which embodies no delicate parts such as are likely to get out of order after a short period of use. a

The invention in all of its details will be fully understood from the following description and claims when the same are read in connection with the accompanying drawings, forming part of this specification, in which:

Figure 1 is a plan view of the adding and subtracting machine constituting the best practical embodiment of my invention that 1 have as yet devised.

Fig. 2 is a side elevation of the same.

Fig. 3 is a fragmentary horizontal section taken in a plane above. the actuating belts and working units and illustrating a sulficient number of divisions comprising said elements to make clear the operation of my novel mechanism.

Fig. 4 is a longitudinal vertical section of the machine.

Fig. 5 is a detail section showing some of the idler sprockets on their shaft.

Figs. 6 and 7 are details illustrative of the projections on the actuating belts.

Figs. 8 and 9 are detail views of the gears that are equipped with supplemental teeth in the form of lateral projections.

Fig. 10 is a fragmentary transverse section, showing in detail the channeled plate that is carried at the underside of the casing to imilar numerals of. reference designate corresponding parts in all of the views of the drawings.

In the preferred embodiment of my invention the machine casing is made of metal and is characterized by a rounded forward cor- Speciflcation of Letters Patent.

Patented Feb. 26, 1918.

Application filed August 25, 1916. Serial No. 116,821.

ner 1 in which are small circular openings 2, and a flat top wall 3 in which are nine (more or less) slots 4.; each slot being inlongitudinal alinement with one opening 2. There is one of the slots 4 for each division of the machine, and the said slots are respectively divided into equal parts and numbered at their opposite sides; the numbers on the right hand sides serving in the operation of the machine for adding, and the numbers at the left hand sides being designed for use in the reverse direction when the machine is manipulated for subtracting. I

Only the first and last slots are shown in Fig. 1 as provided with reversely arranged numbers but it will be understood that in practice all of theslo'ts will be provided with reversely arranged numbers similar to those of the first and last slots.

Fixed to and arranged under the top wall 3 of the casing is a plate 5 in which are grooves 6, one under each slot 4;, for the reception and movement of the upper stretches of belts 7 which correspond in number to the slots 4 and the divisions of the machine. The belts 7 are identical in construction and therefore a detailed description of the one shown in Figs. 4, 6 and 7 will 'sufiice to impart a definite understanding of all. The belt 7 referred to is made of any material possessed of the requisite flexibility and durability. It is provided at intervals in its length with apertures 8 for the outward passage of projections 9 which projections form the stems of T members, the transversely disposed heads 10 of which are arranged and suitably fastened against the inner side of the belt and are V shaped in cross section to fit in the interdental spaces of revoluble elements hereinafter described. The projections 9 are adapted to longitudinally traverse one of the slots 4 and are placed a distance apart corresponding to the distance between the graduations or divisions complementarv to the slot. By virtue of the stems of the T -members resting in apertures in the belt 7 the T-members asslst in connecting themselves to the belt 7 and at the same time take all strain off the fastening means between the heads 10 and the belt, which. fas

tening means may be of any suitable character, when said heads 10 engage the sprocket wheels complementary to the belt.

Formed in the side walls of the machine casing adjacent tothe rear endthereof are slots 11 to receive the rear axle 12 and to permit of the adjustment of the said axle with a view to regulating the tension of the belts 7. On the said axle 12 are looselymounted idler sprockets 13, one for each belt 7, and each having ten teeth to engage in the spaces between the belt heads 10. The said idler sprockets are maintained in spaced relation to each other by loose washers 14; interposed between them, and the sprockets adjacent to the side walls of the casing are prevented from contacting with said side walls through the medium of comparatively thin washers 15, Fig. 5.

Within the casing and at points in front of the slots 4 the belts 7 are supported by ten-toothed sprocket wheels 16 of which there is one in each working unit; the said unit comprising in addition to a sprocket wheel 16, a thin plain wheel 17 to the left of the sprocket wheel 16, a gear wheel 18, having ten teeth or a multiple of ten teeth, at the left of the plain wheel 17, and a lateral extension 19 toward the left on a tooth or teeth of the gear wheel 18; the said tooth or teeth of the extension bein equal to one tenth of the number of teetl i in the gear wheel attached to the right hand side of the number-ring in front of and at the left of the working unit just described. The extension 19 referred to will upon each revolution of its sprocket wheel 16 come into gear with the gear wheel attached to the right hand side of the next higher number-ring and move said number-ring through onetenth of its circumference. sprocket wheel 16, plain wheel 17, gear wheel 18 and lateral extension 19 of each working unit are securely fastened together, and the said working units are maintained in proper relation on a transverse shaft 20 by spacing washers 21 and 21. It will thus be seen that the working units referred to constitute a transverse section of elements in which there are sprocket wheels 16 correspondin in number to the slots 4 and the belts 7; a so, that the washers 21 are next to the side walls of the casing.

In front of the transverse section of elements described there is another transverse section .or series of working units on a transverse shaft 22. Of these working units at the front of the machine, the one toward the right or in the first division of the machine is made up of a thin plain wheel '23 at the right,-a number-ring 24 z. 6., a ring'bearin numbers on its perimeter, in the middle, an a gear wheel 25 at the left, these elements being fixed together, and the gear wheel having ten teeth or a multiple of ten teeth and being intermeshed with the gear wheel 18 of the first workin unit toward the right of the previously escribed transverse section or series of working units. All of The said the other working units in the front section multiple of ten teeth. The said working unit at the left of the section or series, Fig. 1, has a gear wheel 25 at the right of its number-ring 24 but none at the left of said number-ring. -Thin washers 26 are provided between the working units of the front section or series of the machine, to prevent contact during theworkin of the machine. I would also have it un erstood that the number-rings each bear the numerals 09, and that in the front transverse section or series as in the second transverse section or series from the front there is one working unit in each division of the machinei. 6., one workin unit in longitudinal alinement with each s 0t 4: and each belt 7, and so arranged that the numerals on the numberrings are displayed through the casing openings 2 which openings may be glazed or left unglazed in the discretion of the manufacturer of the machine. I would further have it understood that it is manifestly unnecessary to have an extension 19 on the gear wheel 18 at the left of the second transverse section or series of elements from the front.

My novel machine is actuated through the medium of the belts 7, the belts bein moved as desired by an implement engage with one of the belt projections 9 and moved in one of the casing slots 4.

Incidental to the operation of the machine in adding and subtracting, it will be manifest that the working units in the second transverse section or series from the front will be actuated directly by the belts, and will, in turn actuate the working units in the front transverse section or series in the manner and for the purpose described.

I have entered into a detailed description of the construction and relative arrangement of the parts com rised in the present and preferred embo iment of my lnvention in order to impart a full, clear and exact understanding of the said embodiment. I do not desire, however, to be understood as confining myself to the said specific construction and relativearrangement of parts as in the future practice of the invention such changes or modifications may be made, as fairl fall within the scope of my appended c aims.

For instance the machine may embody any desired number of divisions according to the work for which it is especially designed; also, any suitable means may be employed to support the rear portions of the actuating belts so long as the said means is compatib with the purpose of my instood that the numerals and the number rings may be varied as needed to meet different contingencies and that various minor details of construction may be changed as are expedient in practice.

Having described my invention, what I claim and desire to secure by Letters Patent is:- I

1. In a calculating machine, the combination of suitably supported sprocket wheels having spaced recesses in their peripheries, a belt surrounding said sprocket, wheels and having spaced apertures, and T-members having stems extending outwardly through said apertures of the belt to form finger pieces, and also having transverse heads fastened to the inner side of the belt and adapted to seat in the recesses of the sprocket wheels; the extension of the stems through the apertures of the belt serving to assist in the connection of the T-members to the belt and to take strain 03 the fastenin means between the transverse heads and t e belt.

2. In a calculating machine, the combinationof suitably supported sprocket wheels having spaced recesses, of V-shape in crosssection, in their peripheries, a belt surrounding said sprocket wheels and having spaced apertures, and T-members having stems extending outwardly through sai apertures of the belt, to form finger pieces, and also. having transverse heads, of shape in cross-section, fastened to the inner side of the belt and adapted to seat in the recesses of the sprocket wheels, for the purposes set forth. In testimony whereof I aifix my signature in presence of two witnesses.

JESSE L. POOLE.

v Witnesses:

L. SPERATI, A. L. MODANNAID. 

